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    <title>Convert Meta Tags</title>
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<h1>Convert Meta Tags</h1>
<h2>Configuration</h2>
<p>
The 'Convert Meta Tags' filter is enabled by specifying:
<dl>
  <dt>Apache:<dd><pre class="prettyprint"
     >ModPagespeedEnableFilters convert_meta_tags</pre>
  <dt>Nginx:<dd><pre class="prettyprint"
     >pagespeed EnableFilters convert_meta_tags;</pre>
</dl>
<p>
in the configuration file, but it is also enabled automatically by the core
filter set.
</p>

<h2>Description</h2>
<p>
The 'Convert Meta Tags' filter adds a response header that matches each meta
tag with an http-equiv attribute.  For example, HTML
<pre class="prettyprint"
     >&lt;meta http-eqiv="Content-Type" content="text/html; charset=UTF-8"&gt;</pre>
would add an HTTP header:
<pre class="prettyprint"
     >Content-Type: text/html; charset=UTF-8</pre>
in the response headers.
</p>
<p>
The original tag is left unchanged.
</p>
<p>
Certain http-equiv meta tags, specifically those that specify content-type,
require a browser to reparse the html document if they do not match the headers.
By ensuring that the headers match the meta tags, these reparsing delays are
avoided.
</p>

<h2>Risks</h2>
<p>
This filter is considered minimal risk because at this time,
Content-Type is the only <code>http-equiv</code> value that is transformed into
an HTTP header.  Other http-equiv values have been found to have unexpected semantic
implications when transformed to HTTP.
</p>

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